Iowa Admin. Code r. 567-73.31

Current through Register Vol. 47, No. 8, October 30, 2024

Rule 567-73.31 - Dam safety inspection program

(1)Scope of dam safety inspection program. Dams subject to inspection under these rules are regulated dams as defined in this chapter. The scope of department staff field inspections normally is limited to visually observable features of dams and their appurtenant structures.

(2)Purpose of dam safety inspection program. The general purposes of inspections are as follows: to evaluate the construction, operation, and maintenance of dams; to identify observable deficiencies in dams or appurtenant structures; and to identify other floodplain structures or uses which may affect the hazard potential of a dam or use of an associated impoundment. Inspection reports shall be used by the department in determining whether a proposed dam project complies with applicable criteria and to determine whether any of the following conditions exist:

a. A permit violation;

b. A violation of law which requires that a permit be obtained; or

c. A condition which constitutes a public nuisance by causing unacceptable risk of injury to the public health, safety or welfare.

(3)Inspections of significant hazard and high hazard dam structures.

a.Inspection prior to construction. A field inspection may be made by the department to determine the hazard potential of the dam and verify the location and plan information upon receipt of an application for approval of construction or modification of a dam.

b.Inspection during construction. Construction or modification of a dam structure shall be inspected by an engineer licensed in the state of Iowa or by a trained inspector under the supervision of the engineer. After completion of construction or modification of a dam structure, the engineer shall prepare and submit a construction report, as-built plans, and a statement that in the engineer's professional opinion the work was conducted in general conformance with the approved plans and specifications.

c.Acceptance inspections. When construction of a dam or modifications thereto is completed, and as-built plans and a construction report have been submitted, the department shall make a field inspection to determine whether visually observable features of the dam and appurtenant structures are consistent with the approved plans and the conditions of the dam construction permit. The department shall thereafter issue the water storage permit or a letter stating that additional work is required for acceptance of construction. Closure of the low-level outlet gate shall not begin until the department has issued the water storage permit.

d.Periodic inspections after acceptance. High hazard structures shall be inspected at least once every two years by the department. Significant hazard structures shall be inspected at least once every five years by the department. Structures poorly maintained or those that require repairs identified by the department shall be inspected more frequently until required maintenance and repairs are completed. The department shall notify the dam owner or agent before each inspection. Each inspection shall assess the condition of the dam and appurtenant structures and the adequacy of operation and maintenance practices. The inspection may include reevaluation of the ability of the dam and appurtenant structures to adequately withstand the hydraulic loadings and pass the appropriate design floods.

(4)Inspections of low hazard dams.

a.Preliminary site evaluation. The department may evaluate the site of a proposed dam from maps and aerial photographs in lieu of a field inspection.

b.Inspection during construction. The applicant shall be responsible for providing supervision of construction by a person experienced in the type of construction involved.

c.Inspection of dams with operating plans. Low hazard dams with operating plans shall be inspected by the department at least once every five years. Any problems noted shall be reported to the dam owner in writing.

d.General inspections of low hazard dams. Low hazard dams may be periodically inspected by the department to determine their condition. Any serious problems noted shall be reported to the dam owner in writing.

(5)Special inspections and investigations. Special inspections and investigations shall be made by department personnel in the following instances:

a. Upon notice or evidence of unauthorized construction;

b. Upon notice or evidence that a dam has failed or is in a condition where failure appears likely, and public damages would result from such failure; or

c. Upon notice or evidence that the hazard classification of a dam may no longer be valid due to changes in downstream conditions.

(6)Inspections by others. At the discretion of the department, an inspection report submitted by a qualified individual may be accepted in lieu of an inspection and report by the department.

(7)Inspection reports. The department shall prepare a report of each inspection and provide a copy to the dam owner. The report shall state the deficiencies observed during the inspection. If appropriate, the report shall detail the actions required to address the noted deficiencies.

Iowa Admin. Code r. 567-73.31

Amended by IAB September 8, 2021/Volume XLIV, Number 5, effective 10/13/2021